One-Drop Multiplexed Biosensing: A Magnetoelastic Platform with Dual-Mode Readout for Parallel Multi-Virus Detection

The frequent outbreaks of viral diseases in recent years have posed significant threats to the sustainable development of animal husbandry, resulting in substantial economic losses. The escalating complexity of multi-virus coinfections in swine populations necessitates the development of advanced multiplex detection platforms. Therefore, this research presents a novel dual-mode magnetoelastic (ME) sensing platform with multiple reaction chambers, for parallel multi-virus detection. The dual-mode signal output based on frequency signals and visual colorimetric signals can improve detection accuracy and reliability through complementary cross-verification, while also mitigating the limitations associated with single-mode approaches. Based on the magnetoelastic property of Metglas 2826 chip, that is, load mass changes lead to resonance frequency shift (RFS), the virus concentration can be quantified by RFS. The sandwich immunoassay structure of antibody/virus/enzyme-labeled antibody was applied to amplify the signal, and based on the mechanism of enzyme-catalyzed to produce colored substance, enabling visual colorimetric readout. The ME biosensor consisted of a Printed circuit board (PCB)-embedded planar coil array and a PDMS membrane with microchannels and multiple reaction chambers embedded with the Metglas 2826 chip, enabling parallel multi-virus detection in one-drop, and significantly improving the detection efficiency. The ME biosensor achieves a broad detection range (100 pg/mL-1µg/mL) for the detection of African Swine Fever Virus (ASFV) P72, Porcine Parvovirus (PPV) VP2, and Porcine Circovirus (PCV) CAP2, with the detection limit of 100pg/mL. This integrated ME sensing platform provides a low-cost, high-sensitivity, portable method adaptable to complex environments for the parallel multi-virus detection, demonstrating significant potential for on-site multiplex pathogen screening in veterinary diagnostics and epidemic control.